Process of treating alloys.



UNITED STATES 'PATENTOFFICE;

HAROLD EDWIN CLEAV E S, OF WASHINGTON, DISTRICT OF COLUMBIA.

rioonss or TREATING'ALLOYS.

I Drawing.

To all whom it may camera:

Be it known that I, HAROLD EDWIN CLEAVES, a citizen of the United States, re-

siding at Washington, in the District of 5 Columbia, haveinvented new and useful Improvements in Processes of Treating Alloys, of which the following is a specification.

This invention relates to a rocess of separating from each other meta s which are intimately associated in their metallic state; and it comprises subjectin such a metal mixture to the action of a ydrogen halid, such as hydrogen chlorid, while maintaining the mixture at a temperature, usually above a red heat, at which at least one-of the metals will be converted into a metal halid and volatilized.

The alloys and metal compositions with which the resent process is chiefly concerned are t ose containing on the one hand ametal which is com aratively chemically inactive in the metal '0 state, such as the metals of the fifth and sixth groups of the periodic system, and particularly the metals: vanadium, chromium, molybdenum, and tungsten; and on the other hand, a metal such as iron which is comparatively active, and which will combine readily with hydrogen chlorid to form a metal chlorid'. so The ferro-alloys such as ferrochromium,

ferrotungsten, etc., obtainable, for instance,

' by reduction of their corresponding oxygen salts (chromites, tungstates) can be treated with great advantage by this process, the resulting products having a very low iron content, as well as adecreased fpercentage of sulfur, arsenic and oxygen i these metalloids were present in the original alloy.

The manner in which m process is car- 40 ried out may be illustrated y the following examplesz.

Example I: A ferrotungsten, finely subdivided," containin about 70% tungsten,

Y 25% iron, 1-2% W and small proportions 46 of sulfur and manganese, is maintained at a tem erature of about 1100 C. and a stream of ydrogen chlorid gas passed over the heated material. The iron in the alloy is rapidly converted into iron chlorid, vo a Q0 lized and removed by the stream of gas, the

' impurities ox gen, manganese, and sulfur being remove at the. same time. The resulting product is almost pure metallic tungsten. The tungsten whie was present 56 as tungsten oxid is converted into tungsten chlorid and volatilized, but may be easily re- Specification of Letters Patent.

' Patented Aug. '7, 191 7.

Application filed May 28, 1917. Serial No. 170,522.

iron is volatililzed as iron chlorid and any molybdenum which was present as oxld is also volatilized in its chlorid form. The reaction is discontinued when the molybdenum content of the ferromolybdenum has been raised to about 90%, which can be accomplished in a comparatively short time. 7

Example III: Finely divided ferrochrome containing about chromium is maintained at a temperature of about 1050 C.

"while hydrogen chlorid is passed in contact therewith. In this case both the chromium. and iron are converted into their chloride,-

but onl the iron chlorid is v'olatilized. A very e ective se aration of the iron and chromium is there y obtained, the chromium being in a form readily convertible into other valuable chromium compounds.

Example IV: Ferrovanadium, suitably comminuted, and containing about vanadium, is maintained at a tem erature of about 1050 C. while a stream 0 hydrogen chlorid is passed in contact therewith, The iron is volatilized as the chlorid, leaving metallic vanadium from which most, if not all, of the iron has been removed. Any purities such as oxygen and sulfur are re moved at the same time.

My invention includes a fractional, as well as a complete, removal of one of the components of the metal mixture or alloy, since in many cases the presence of one of the components, such as lron, in small proportions is not objectionab e.

What I claim is 1. The process of treating a metal mirture or al 0y to reduce the content of one of the component metals, at least one of the component metals being capable of reach ing with hydrogen halid to form a metal halid volatile at a high temperature, which comprises subjecting the suitably subdivided metal mixture to the action of hydrogen halid while maintaining said mixture at a temperature at which the halid of at least one of the metals is formed and volatilized.

2. The process of treating a metal mix ture or alloy to reduce the content of one of the component metals, at least one of the fifth and sixth component metals being capable of reacting wlth hydrogen chlori'd to form a metal chlorid volatile at a high temperature,

which comprises subjecting the suitably subdivided metal mixture to the action of hydrogen chlorid While maintaining said mixture at a temperature at Which the chlorid of at least one of the metals is formed and vo1ati1ized.-

3. The process of treating metals of the groups of the periodic system intimately associated with a metal capable of reacting with hydrogen chlorid to form a metal chlorid, which comprises passing hydrogen chlorid in contact with the finely divided metal mixture, While maintaining the latter at a temperature at which said metal chlorid Will be formed and volatilized.

at. The process of reducing the iron content of a. ferro-alloy of vanadium, tungsten 1 or molybdenum, which comprises passing hydrogen chlorid in contact with said alloy While maintalnlng the latter at a temperature at which iron chlorid will be formed and volatilized.

5. The process of reducing the iron content of a ferro alloy of vanadium, tungsten or molybdenum, which comprises passing hydrogen chlorid in contact with said alloy while maintaining the latter at a temperature of about from 1000 to 1100 C.

6. The process of reducing the iron content or a ferrotungsten which comprises passing hydrogen chlorid in contact with finely divided ferrotungsten While maintaining the latter at a temperature at which iron chlorid will be formed and volatilized.

7. The process of removing iron from a ferrotungsten containing more tungsten than iron, which comprises subjecting said ferrotungsten, in a suitablyfinely divided condition, to the action of hydrogen chlorid While maintaining the ferrotungsten at a temperature of about 1000 to 1100 C.

In testimony whereof I afiix my signature.

HAROLD EDWIN CLEAVES. 

